Nicotinic acetylcholine receptors (nAChR) form a family of ion channels activated by acetylcholine. Functional receptors contain five subunits and there are numerous receptor subtypes. Studies have shown that central nicotinic acetylcholine receptors are involved in learning and memory. Nicotinic acetylcholine receptors of the alpha7 subtype are prevalent in the hippocampus and cerebral cortex.
WO 2003/055878 describes a variety of agonists of the alpha7 nAChR said to be useful for improving cognition. WO 2003/055878 suggests that certain agonists of the alpha7 nAChR are useful for improving perception, concentration, learning or memory, especially after cognitive impairments like those occurring for example in situations/diseases/syndromes such as mild cognitive impairment, age-associated learning and memory impairments, age-associated memory loss, Alzheimer's disease, schizophrenia and certain other cognitive disorders. Among the compounds described are (R)-7-chloro-N-(quinuclidin-3-yl)benzo[b]thiophene-2-carboxamide and pharmaceutically acceptable salts thereof.